[PATCH v1] iio: temperature: hid-sensor-temperature: switch to non-devm iio_device_register()

[PATCH v1] iio: temperature: hid-sensor-temperature: switch to non-devm iio_device_register()

[Sanjay Chitroda]

From: Sanjay Chitroda <sanjayembeddedse@gmail.com>

Avoid using devm_iio_device_register(), as this driver requires explicit
error handling and teardown ordering.

Mixing devm_* APIs with goto-based error unwinding breaks the expected
LIFO resource release model and can introduce race windows during device
removal. In particular, the IIO device may remain visible to userspace
while dependent resources are already being freed, potentially leading
to use-after-free issues.

Add explicit iio_device_unregister() call in the teardown path to ensure
deterministic cleanup and follow kernel resource management conventions.

Fixes: 59d0f2da3569 ("iio: hid: Add temperature sensor support")
Signed-off-by: Sanjay Chitroda <sanjayembeddedse@gmail.com>
---
 drivers/iio/temperature/hid-sensor-temperature.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/temperature/hid-sensor-temperature.c b/drivers/iio/temperature/hid-sensor-temperature.c
index 9f628a8e5cfb..34bff7e9f3a3 100644
--- a/drivers/iio/temperature/hid-sensor-temperature.c
+++ b/drivers/iio/temperature/hid-sensor-temperature.c
@@ -244,7 +244,7 @@ static int hid_temperature_probe(struct platform_device *pdev)
 	if (ret)
 		goto error_remove_trigger;
 
-	ret = devm_iio_device_register(indio_dev->dev.parent, indio_dev);
+	ret = iio_device_register(indio_dev);
 	if (ret)
 		goto error_remove_callback;
 
@@ -264,6 +264,7 @@ static void hid_temperature_remove(struct platform_device *pdev)
 	struct iio_dev *indio_dev = platform_get_drvdata(pdev);
 	struct temperature_state *temp_st = iio_priv(indio_dev);
 
+	iio_device_unregister(indio_dev);
 	sensor_hub_remove_callback(hsdev, HID_USAGE_SENSOR_TEMPERATURE);
 	hid_sensor_remove_trigger(indio_dev, &temp_st->common_attributes);
 }
-- 
--

Re: [PATCH v1] iio: temperature: hid-sensor-temperature: switch to non-devm iio_device_register()

[Andy Shevchenko]

On Mon, Jun 22, 2026 at 10:51:35AM +0530, Sanjay Chitroda wrote:

> Avoid using devm_iio_device_register(), as this driver requires explicit
> error handling and teardown ordering.
> 
> Mixing devm_* APIs with goto-based error unwinding breaks the expected
> LIFO resource release model and can introduce race windows during device
> removal. In particular, the IIO device may remain visible to userspace
> while dependent resources are already being freed, potentially leading
> to use-after-free issues.
> 
> Add explicit iio_device_unregister() call in the teardown path to ensure
> deterministic cleanup and follow kernel resource management conventions.

Strictly speaking this needs Cc: stable@ as well as mentioned in the
documentation.

LGTM,
Reviewed-by: Andy Shevchenko <andriy.shevchenko@intel.com>

-- 
With Best Regards,
Andy Shevchenko